The leader of the United States encouraging law enforcement and the military to shoot American citizens for looting, that's the line.
That's an extremely literal interpretation of his words. Most people would interpret that phrase to mean "you better think twice before looting because I'm not going to sit idly by and let you do it" but in the form of a vaguely threatening, yet catchy rhyme.
What do you base the knowledge of how most people will have interpreted this statement on?
The historical experiences of different classes of people can have a profound impact on the perspectives they have in relation to the government. An 80 year old black man might have a very different relationship with governmental authorities than a 30 year old Latino, or a 40 year old Caucasian.